This invention relates to vehicle automated guidance control systems. Specifically, the present invention relates to an apparatus and a method that assures the safe operation of a vehicle when the vehicle is under the control of a guidance control system.
Tractors and other vehicles used in farming operations must be operated precisely to obtain uniform rows during planting and to harvest crops efficiently. Typically tractors used for planting rows of crops are operated manually by an operator who drives the tractor along each row to be planted. The operator must be very careful in order to get uniform rows of planted crops. It is difficult for an operator of a tractor to maintain precise positioning of the tractor relative to rows that have already been planted since the operator has no reference other than the position of the row that was most recently planted to use as a guide. In addition, it is difficult to maintain the concentration necessary to obtain straight rows, particularly since concentration often decreases with each passing hour of planting.
One prior art method for controlling the travel path of a vehicle such as a tractor includes the use of a guidance control system that includes an automatic steering control feature. These guidance control systems typically include a position determining system for determining position and a vehicle controller for controlling the steering of the vehicle. One method for position determination involves the use of satellites of the US Global Positioning System (GPS) to determine position. However, other types of position determination systems may also be used. The guidance control system typically includes a vehicle controller operable in response to an operator input mechanism and a display.
Once the operator is properly positioned and is ready to start planting a row, he operates an input device so as to activate the automatic steering control feature of the guidance control system. The automatic steering control feature of the guidance control system operates the steering of the tractor so as to maintain proper alignment of the vehicle as a row is planted.
Once the automatic steering control feature is engaged, the tractor moves up and down each row and performs the steering automatically. In many tractors equipped with automatic steering control, cruise control is also provided. Thus, the operator is only required to monitor the automated steering control and the cruise control. Typically, tractors under automated steering control operate at a speed of 3 to 6 miles per hour and as high as 20 miles per hour.
Though these prior art systems effectively and efficiently perform the desired operations, operators often become bored and inattentive. Sometimes operators will attempt to leave the tractor as it is operating. This may be for the purpose of removing obstructions that lie in the path of the tractor, taking a lunch break, talking with a friend, etc. The operator may be injured as he attempts to climb down from the moving tractor. In addition, the operator may be run over by the tractor or equipment attached to the tractor as he attempts to get off the tractor.
Injury can also occur as the operator tries to climb back onto the moving tractor. More specifically, the operator can fall as he attempts to board the moving tractor, resulting in the operator being struck by the tractor. This can result in serious injury and even death.
Injuries may also occur while the tractor is stationary. When a tractor is stopped and the automatic steering control feature is engaged, voltage spikes, hardware, firmware, and software malfunctions may occur. These malfunctions may result in injuries. When an operator is attempting to fix a problem or a malfunction on the tractor, malfunctions may result in the movement of the tractor which can cause the movement of the steering system. The movement of the steering system and/or the tractor itself can cause the operator to be crushed or injured by the movement. One particularly dangerous type of movement of the steering system is commonly referred to as xe2x80x9crailing.xe2x80x9d Railing is the sudden movement of the steering system fully to one side or the other.
Malfunctions in hardware, firmware, and software may also cause injury and possibly property damage during proper operation of the tractor. For example, when the automated steering control is in operation and a malfunction occurs, unintended movement of the steering system may result. This can cause damage to crops, injury, collision of the tractor, and in some instances may cause the tractor to flip over. Malfunctions that result in railing of the steering system are particularly likely to cause injury since the tractor is likely to flip over or collide with objects or vehicles.
What is needed is a way to assure the safety of a vehicle that has a guidance control system. More particularly, a way to prevent malfunctions from injuring an operator both when the tractor is moving and when the tractor is stationary is needed. In addition, a safety system is needed to prevent an operator from leaving a tractor while the automated steering control is engaged. The present invention meets the above needs.
The present invention provides a method and apparatus which provides for safely operating a vehicle when the automatic steering control feature of a guidance control system is engaged.
A safety system is disclosed that is electrically coupled to the vehicle""s guidance control system. The safety system includes one or more sensors that are monitored so as to determine whether the operator is in the vehicle. In one embodiment, the sensors include a dead-man switch that must be periodically operated by an operator.
When the safety system detects that the operator is attempting to leave the vehicle when the automatic steering control feature of the guidance control system is engaged, the safety system either shuts off the vehicle or disengages the automated steering control feature. This prevents the operator from leaving a moving tractor since the tractor will not continue to operate without the operator""s presence. Thus, potential injury and property damage are avoided.
The safety system of the present invention also prevents movement of the vehicle""s steering system when the vehicle is stopped. This allows for safe vehicle repair and maintenance and prevents accidents resulting from tampering with the vehicle""s guidance control system components.
Though the present invention is described with reference to use in a vehicle which is a tractor, the present invention may be used in other types of vehicles such as, for example, harvesters, wind rowers, spray rigs, fertilizer delivery vehicles, pesticide delivery vehicles, track vehicles, belt driven tractors, and harvest collection vehicles such as general purpose trucks, flat bed trucks, and tractor-trailer rigs.
These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments that are illustrated in the various drawing figures.